1. Field of the Invention
The present invention is directed to a self-powered, self-contained mobile dredge apparatus which is substantially submersible and is adapted to be driven along the bottom surface of a body of water, such as a canal, for removing a bottom layer of accumulated silt and other sediment resulting from erosion caused by rain and irrigation, while simultaneously dispersing a mixture of the bottom sediment and water effectively across the surrounding terrain.
2. Description of the Related Art
In order to provide sufficient water to growing crops, it is common for many plantation fields to be equipped with irrigation systems which deliver and disperse large quantities of water throughout the field. It is also common for plantation fields, such as banana plantations and sugar plantations, to be located in climates which produce a significant amount of annual rainfall, thus subsidizing the irrigation systems. In order to properly drain the water supplied through irrigation and rainfall, most plantation fields, and specifically banana and sugar plantations, include drainage canals extending in spaced, parallel relation through the fields. Any excess runoff of rain and irrigation water fills into the canals and flows downstream where, once collected, it might be resupplied throughout the fields through the irrigation system.
A common problem associated with virtually all drainage and irrigation canals in plantation fields is blockage resulting from a build-up of silt which deposits on the bottom of the canals due to erosion of topsoil caused by rain and irrigation. In order to ensure that the canals remain at a predetermined depth and therefore function properly, it is required to periodically remove the silt build-up from the bottom of the canals, redepositing the soil back onto the bordering plantation field. Ordinarily, this is achieved by either removing the accumulated silt build-up manually with shovels or through the use of a back hoe positioned along a bank of the canal. In either event, the removed silt is thereafter deposited into piles or mounds along the banks of the canal. It is thereafter required to disperse the piles of soil evenly across the surrounding plantation fields in order to prevent rapid and excessive erosion along the canal banks. In using a back hoe, the bottom sediment is removed in bulk, and it is common that large rocks, sticks, and other undesirable objects are removed along with the bottom sediment. The removed sediment must then be filtered, usually by laborers who sift through the mounds with their feet, prior to dispersing throughout the fields, in order to separate large objects, such as rocks, which might damage harvesting machinery used in the plantation fields. Accordingly, there are generally two distinct and separate processes which are ordinarily employed in order to maintain drainage canals at a predetermined depth, namely removing the accumulated silt build-up from the bottom of the canals and subsequently dispersing the piles of soil from along the canal banks. And, in using a back hoe it is also necessary to filter the sediment prior to dispersing in order to remove large objects. This practice has proved to be extremely time-consuming and expensive, requiring a considerably large number of laborers whose progress is limited to a large extent by the process employed and equipment being used. Because many plantation fields, such as banana plantations, are located in rainy climates, the rate of erosion is rather rapid and, when coupled by the rate at which the canals can be cleared, the maintenance of the canals becomes a constant problem. Further, in climates having heavy rainfall, the ground pressure is usually not sufficient to handle heavy equipment such as back hoes which, weighing approximately 30,000 to 50,000 pounds, tend to sink in the soil along the canal banks. This further adds to the time-consuming task of clearing the canals, requiring most of the work to be performed manually.
Other methods of clearing drainage canals have employed the use of dredges on pontoons or other similar floating structures which are navigated along the canals, while a pump is used to suck the accumulated silt from the bottom of the canal. In most instances, the bottom sediment is then discharged through pipes which lead to a distant location. As the floating dredge progress along the canal, a considerable number of laborers are needed in order to disassemble the pipes, move them and reassemble a new pipe line leading from the repositioned dredge. A common problem encountered when using dredges of this type, which float on the surface of the water, is the inability to move the dredge unit against the layer of accumulated silt build-up in a matter which effectively force feeds the pump and thereby accelerates the dredging process. A further problem is encountered in dry seasons when using floating dredge assemblies, due to the usual low water level in the canals which prevents navigation of the floating dredges therealong. And of course, a common problem associated with all of the equipment in the related art is the difficulty in transporting the equipment between adjacent canals.
In view of the aforementioned problems presently associated in removing bottom sediment and silt build-up on the bottom of drainage canals, it is an object of the present invention to provide a fully mobile, totally submersible dredge apparatus which is structured to be driven on the bottom surface of canals to rapidly remove accumulated silt build-up on the bottom of canals while simultaneously returning and dispersing the silt evenly across the surrounding terrain.
It is another object of the present invention to provide a self-contained, self-powered dredge apparatus which is adapted to be driven into and out of canals and across terrain between canals thus effectively reducing the time and labor involved in transporting equipment.
It is a further object of the present invention to provide a submersible dredge apparatus which includes a high torque submersible track drive system which is structured to move the dredge apparatus along virtually any terrain, including a bottom surface of the canal, force feeding the accumulated bottom sediment and silt build-up into a dredge unit thereof, while the track drive system simultaneously compacts the dredged canal bottom.
It is yet a further object of the present invention to provide a compact, self-powered and self-contained dredge apparatus which is easily navigable through narrow drainage and irrigation canals and through surrounding plantation fields.
It is still a further object of the present invention to provide a self-powered, self-contained dredge apparatus which is structured to rapidly and efficiently remove accumulated bottom sediment and silt build-up from the bottom of drainage and irrigation canals, while simultaneously dispersing a slurry made up of at least 40% solids evenly across the surrounding terrain.
It is a further object of the present invention to provide a self-powered, compact, highly maneuverable dredge apparatus which is structured to effectively operate in a body of water, such as a canal, having a minimum water level of 4".
These and other objects and advantages of the present invention will be more readily apparent in the description which follows.